//==========================================================================
// Copyright (c) 2000-2008,  Elastos, Inc.  All Rights Reserved.
//==========================================================================
/* $Id: jffs2_fs_sb.h,v 1.2 2006/05/16 14:14:36 shijun Exp $ */

#ifndef _JFFS2_FS_SB
#define _JFFS2_FS_SB

#include "jffs2_list.h"
#include "jffs2_spin_lock.h"
#include "jffs2_wait.h"
#include "jffs2_semaphore.h"

#define JFFS2_SB_FLAG_RO 1
#define JFFS2_SB_FLAG_SCANNING 2 /* Flash scanning is in progress */
#define JFFS2_SB_FLAG_BUILDING 4 /* File system building is in progress */

struct jffs2_inodirty;

/* A struct for the overall file system control.  Pointers to
   jffs2_sb_info structs are named `c' in the source code.  
   Nee jffs_control
*/
struct jffs2_sb_info
{
    struct mtd_info *mtd;

    uint32_t highest_ino;
    uint32_t checked_ino;

    unsigned int flags;

    //struct task_struct *gc_task; /* GC task struct */
    //struct completion gc_thread_start; /* GC thread start completion */
    //struct completion gc_thread_exit; /* GC thread exit completion port */

    struct semaphore alloc_sem; /*Used to protect all the following 
                       fields, and also to protect against
                       out-of-order writing of nodes. And GC. */
    uint32_t cleanmarker_size; /*Size of an _inline_ CLEANMARKER
                     (i.e. zero for OOB CLEANMARKER */

    uint32_t flash_size;
    uint32_t used_size;
    uint32_t dirty_size;
    uint32_t wasted_size;
    uint32_t free_size;
    uint32_t erasing_size;
    uint32_t bad_size;
    uint32_t sector_size;
    uint32_t unchecked_size;

    uint32_t nr_free_blocks;
    uint32_t nr_erasing_blocks;

    /* Number of free blocks there must be before we... */
    uint8_t resv_blocks_write; /* ... allow a normal filesystem write */
    uint8_t resv_blocks_deletion; /* ... allow a normal filesystem deletion */
    uint8_t resv_blocks_gctrigger; /* ... wake up the GC thread */
    uint8_t resv_blocks_gcbad; /* ... pick a block from the bad_list to GC */
    uint8_t resv_blocks_gcmerge; /* ... merge pages when garbage collecting */

    uint32_t nospc_dirty_size;

    uint32_t nr_blocks;
    struct jffs2_eraseblock *blocks; /* The whole array of blocks. Used for getting blocks 
                         * from the offset (blocks[ofs / sector_size]) */
    struct jffs2_eraseblock *nextblock; /* The block we're currently filling */

    struct jffs2_eraseblock *gcblock; /* The block we're currently garbage-collecting */

    struct list_head clean_list;  /* Blocks 100% full of clean data */
    struct list_head very_dirty_list; /* Blocks with lots of dirty space */
    struct list_head dirty_list;  /* Blocks with some dirty space */
    struct list_head erasable_list;  /* Blocks which are completely dirty, and need erasing */
    struct list_head erasable_pending_wbuf_list; /* Blocks which need erasing but only after the current wbuf is flushed */
    struct list_head erasing_list;  /* Blocks which are currently erasing */
    struct list_head erase_pending_list; /* Blocks which need erasing now */
    struct list_head erase_complete_list; /* Blocks which are erased and need the clean marker written to them */
    struct list_head free_list;  /* Blocks which are free and ready to be used */
    struct list_head bad_list;  /* Bad blocks. */
    struct list_head bad_used_list;  /* Bad blocks with valid data in. */

    spinlock_t erase_completion_lock; /* Protect free_list and erasing_list 
                           against erase completion handler */
    wait_queue_head_t erase_wait;  /* For waiting for erases to complete */

    wait_queue_head_t inocache_wq;
    struct jffs2_inode_cache **inocache_list;
    spinlock_t inocache_lock;

    /* Sem to allow jffs2_garbage_collect_deletion_dirent to
       drop the erase_completion_lock while it's holding a pointer 
       to an obsoleted node. I don't like this. Alternatives welcomed. */
    struct semaphore erase_free_sem;

#ifdef CONFIG_JFFS2_FS_WRITEBUFFER
    /* Write-behind buffer for NAND flash */
    unsigned char *wbuf;
    uint32_t wbuf_ofs;
    uint32_t wbuf_len;
    uint32_t wbuf_pagesize;
    struct jffs2_inodirty *wbuf_inodes;

    struct rw_semaphore wbuf_sem; /* Protects the write buffer */

    /* Information about out-of-band area usage... */
    struct nand_oobinfo *oobinfo;
    uint32_t badblock_pos;
    uint32_t fsdata_pos;
    uint32_t fsdata_len;
#endif

    /* OS-private pointer for getting back to master superblock info */
    void *os_priv;
};

#endif /* _JFFS2_FB_SB */
